Wearing pink, pointy-eared 'p****hats' to mock the new US president, throngs of protesters descended on the US capital and other cities around the globe to showDonald Trump they won't be silent over the next four years.

In more than 600 marches held all over the globe, they carried signs with messages such as 'Women won't back down' and 'Less fear more love' and decried Trump's stand on such issues as abortion, diversity and climate change.

There were early signs that crowds in Washington could top those that gathered for Trump's inauguration on Friday. City officials said organisers of the Women's March on Washington had more than doubled their turnout estimate to 500,000 as crowds began swelling and subways into the city became clogged with participants.

Some 2.2 million people are believed to have marched to promote women's and human rights, with an estimated 100,000 out on the streets in London.

Huge demonstrations have also been held in cities including Paris, Berlin, Edinburgh, Rome, Prague, Amsterdam, Stockholm, Athens, Copenhagen, New Delhi, Brussels, Mexico City, Barcelona, Manila, Toronto, Madrid, Geneva, Cardiff and Sydney on Saturday in opposition to the 45th President of the USA.

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Thousands of protesters packed Trafalgar Square to listen to speeches in London after taking part in the women's march

Swathes of protesters are pictured making their way through the streets of London on Saturday. While the march organisers' 'mission and vision' statement never mentions Trump the unifying factor among those turning out appeared to be a loathing for the new US president

Protesters hold 'nasty women' placards during the Women's March rally, in Geneva, Switzerland

A placard is held aloft in front of the US Embassy in Berlin, where huge crowds gathered for the Women's March

Anti-Trump campaigners gather in front of the US Embassy in Madrid as part of worldwide protests

Protesters linked hands as they demonstrated for women's rights in Brasilia in Brazil, with rallies held in more than 30 countries

A woman in London captured the mood of 100,000 protesters who took to the streets on the first full day of Donald Trump's presidency

Singer Camilla Kerslake and her boyfriend former England rugby captain Chris Robshaw were seen at the march in London

Organisers of London's Women's March have hailed a huge turnout, which saw an estimated 100,000 people pack into Trafalgar Square for a rally at 2pm.

They came holding a rainbow of placards with slogans such as 'dump Trump', 'reject hate, reclaim politics' and 'no to racism, no to Trump'.

Actress Gillian Anderson tweeted that she was proud to take part in the Women's March in London today

Mr Trump's presidential campaign was plunged into crisis after a 2005 tape recording came to light of him bragging to TV host Billy Bush about groping women and that he can 'grab them by the p***y' because of his celebrity status.

Actress Gillian Anderson, star of The X Files and The Fall, who took part in the London march, tweeted: 'Proud to be one of many today.'

Holding a sign saying 'my p****y is not up for grabs', Kim McInally said she had travelled from Brighton to London for the demonstration.

The 32-year-old said: 'Yesterday was seen as the official start of fascism coming back.'

Iron Man 3 actress Rebecca Hall were spotted among the throngs of people. Hall said she joined the march because she is half American and half English, and said if she had been on the other side of her pond she would have joined the Washington DC demonstration.

She added: 'Yesterday was a confusing day and a sad day - I was sad to see Obama leave ... We do not know what the Government is going to be like.'

Labour MP Harriet Harman was joined on the march by friend and American-British playwright Bonnie Greer.

Referring to outgoing US president Barack Obama, Ms Harman said: 'It's just a shame they have a two-term limit, isn't it?'

Girls Just Wanna Have Fundamental Rights: One of the placards held aloft at yesterday's rally in Toronto

A young girl holds a banner stating 'We are stronger than you think' in Toronto

The sign reads 'Paris against Trump' as thousands of protesters gather underneath the Eiffel Tower in the French capital

Actress Scarlett Johansson smiles at the Women's March in Washington, where an estimated 500,000 people took part

Amy Schumer (L) and Madonna were among the celebrities who joined the Women's March on Washington

Actress Helen Mirren gives a thumbs up to the crowds (left) and she is pictured with Sex and the City actress Cynthia Nixon (right)

Singer Tracee Ellis Ross was at the rally in Los Angeles (left), while Alicia Keys was one of the performers in Washington DC (right)

Women in pink 'p***yhats' arrive for Washington march

Huge numbers of American women in pink 'p***yhats' have arrived in Washington DC in protest of the new president on Saturday morning.

Pink 'p****yhats', which are pink knitted beanies with cat ears, have become the unofficial accessory of the march, and were proudly displayed on flights across the country.

One Southwest crew even lit up their plane cabin in pink on Friday night, according to Mashable.

Some photos show women wearing the p***yhats, many also donning Hillary Clinton and 'Nasty Woman' shirts on their way to Washington

Thousands of participants converge on the Women's March on Washington in Washington

In Washington a woman holds a sign saying 'science over opinion' another signs says 'history has its eyes on you'

Women with pink hats and signs begin to gather early and are set to make their voices heard in Washington

The 'P***yhat project' started as a campaign to outfit people marching in the Women's March on Washington.

Groups of women wearing the hats are doing so in order to show solidarity, as well as reclaim the loaded term used by Trump in the now infamous Access Hollywood recording.

Mr Trump's presidential campaign was plunged into crisis after a 2005 tape recording came to light of him bragging to TV host Billy Bush about groping women and that he can 'grab them by the p***y' because of his celebrity status.

A city official in Washington says the turnout estimate for the Women's March on the National Mall now stands at 500,000 people. That's more than double the initial predictions.

Demonstrators arriving at Union Station in Washington carried signs saying '1968 is calling don't answer' and 'sexism is a social disease'

There were early signs across Washington that Saturday's crowds could top those that gathered on Friday to watch President Donald Trump's inauguration.

Metro subway stations and train cars are full in many locations, while ridership on Friday was well off the numbers from Barack Obama's first inaugural.

The march's National Park Service permit estimated a turnout of 200,000, but the District of Columbia's homeland security chief had previously predicted turnout would be higher.

Women with bright pink hats and signs begin to gather early in Washington

The mission statement of the Women's March on Washington says event participants are "hurting and scared" as Donald Trump takes office - and they want a greater voice for women in political life

People arrive on the mall for the march on Washington. Protest rallies were held in over 600 places around the world in solidarity

A man in an orange jumpsuit and a Donald Trump mask (left) and a protester (right) wearing a dark mask were pictured in London

Ms Greer warned that Mr Trump's presidency was 'not a joke', adding: 'This is for real and I think this march demonstrates that London understands that.'

Spectators lining the London route cheered as the protest made its away towards Trafalgar Square.

She claimed 'human rights and human equality is getting pushed further and further down the list'.

Ten-year-old Lily, an American youngster living in Britain said: 'I don't like him at all.' She added that it's important for 'women and girls to have their rights'.

In Cardiff former classical singer Charlotte Church joined around 1,000 protesters on the women's march. Charlotte, 30, joined in chants holding a cardboard sign adorned with the feminist phrase: 'I didn't come from your rib, you came from my vagina.'

Around 1,000 people joined in the rally in Cardiff on Saturday in opposition to the 45th President of the USA

In Cardiff former classical singer Charlotte Church joined around 1,000 protesters on the women's march.

Mum-of-two Charlotte, 30, joined in chants and was holding a cardboard sign adorned with the feminist phrase: 'I didn't come from your rib, you came from my vagina.'

She was dressed in a light brown anorak and wore rounded sunglasses and was wearing a black rucksack.

More than 1,000 people took part in a march in Bristol - with one placard bearing the words 'We Shall Overcomb'

Organiser Carly Wilkinson said: 'I wanted to make the world know that Bristol feels the same as many, that our voices could be heard together'

In Bristol, more than 1,000 people marched from Queen Square to College Green - just 72 hours after the event was organised.

The group chanted and held placards as they took part in the Sister March in solidarity with the Women's March On Washington.

Blogger Carly Wilkinson, 32, began organising the march from her kitchen table in the city on Wednesday.

'I didn't expect to cry but I have just experienced every emotion,' she said.

'I wanted to make the world know that Bristol feels the same as many, that our voices could be heard together.'

Protesters outside the American Embassy in London in a march to promote women's rights in the wake of the US election result

Thousands of protesters make their way through the streets of London during the Women's March on Saturday

An aerial view of central London shows thousands of women and marching through the city on Saturday

Some of the signs referenced Donald Trump's famous combover hairstyle (left) others campaigned against his views on climate change

Protesters carry placards and balloons in London in a march to promote women's rights in the wake of the US election result

A marchers holds up a sign saying 'I am woman hear me roar' as she takes part in the peaceful protest

'Don't just watch - march! This concerns us all,' one sign said as marchers left Grosvenor Square, London. A women dressed as 'the statue of taking liberty' (left) walked with protesters

Hundreds of people walk through Bristol with signs saying 'because I want to march forwards not backwards'

Hundreds of people walk through Bristol in a Women's March, to protest against President Donald Trump on his first full day in power

The rally in Washington kicked off at 10am with a rousing speech from actress America Ferrera.

‘The president is not America, his cabinet is not America,' Ferrera began. ‘We are America, and we are here to stay. We march for our families, for our neighbors, for our futures.’

‘We march today for the moral core of this nation, against which our president is waging a war.'

‘We are gathered here across the country and the world to say Mr Trump we refuse,' Ferrera continued.

The marches were a magnet for A-list celebrities, unlike Trump's inauguration, which had a deficit of top performers.

Alicia Keys sang 'Girl on Fire' for the Washington crowd. Madonna gave a fiery, profanity-laced address to the gathering. Cher, also in the nation's capital, said Trump's ascendance has people 'more frightened maybe than they're ever been'.

In Park City, Utah, it was Charlize Theron leading demonstrators in a chant of 'Love, not hate, makes America great.'

Actresses Helen Mirren and Cynthia Nixon and Whoopi Goldberg joined the crowd of protesters in New York.

Singer Alicia Keys posted this image on Instagram, saying: 'No matter where you were today... We sent a powerful message! I'm proud of everyone who gathered with such dignity and strength to send the message that we won't stop until we are heard!'

Ugly Betty star America Ferrera, who helped organise the Washington protest, spoke in front of a crowd of around 500,000

'We reject the demonization of our Muslim brothers and sisters, we demand an end to the system murder and incarceration of our black brothers and sisters, we will not give our rights to safe and legal abortions, we will not ask our LGBTQ families to go backwards, we will not go from being a nation of immigrants to a nation of ignorance.’

'We won’t build walls and we won't see the worst in each other and we won’t turn our backs on the more than 750,000 young immigrants in this country.'

'Together we, all of us, will fight, resist and oppose every action that threatens the lives and dignity of any and all of our communities.'

'Marchers, make no mistake. We are, every single one of us, on attack. Our safety and freedom are on the chopping block and we are the only ones who can protect one another.'

'If we do not fight together…we will lose together.'

Singer Alicia Keys wrote on Instagram: 'No matter where you were today... We sent a powerful message! I'm proud of everyone who gathered with such dignity and strength to send the message that we won't stop until we are heard!'

Jessica Chastain attended the march with fellow actress Chloe Graze Moretz, sharing a Snapchat story on the way to the protest

Pop star Katy Perry marched in Washington, joining an estimated 500,000 making their feelings about President Trump clear

Left to right, Debbie Mazur, Gloria Steinem, Madonna and, front, Amy Schumer attend the rally at the Women's March on Washington

Music icons Alicia Keys (left) and Cher (right) were among the celebrities who took part in the rally in Washington DC

Yoko Ono arrived at the Women's March in New York. Celebrities Katy Perry, Scarlett Johansson, Amy Schumer and Patricia Arquette were expected to be among the demonstrators at the Washington event

Ashley Judd recited a poem written by a 19-year-old from Tennessee, which included the line: 'I feel Hitler in these streets, a mustache traded for a toupee.'

The poem was a celebration of 'nasty women', as Trump so famously called Hillary Clinton during a debate before the presidential election.

'I am a nasty women,' Judd began as she read the poem. 'I'm not as nasty as a man who looks like he bathes in Cheeto dust.'

Feminist hero Gloria Steinem also addressed the crowd saying: 'Everything that happened before him was a disaster and everything that he would do would be fantastic, the best ever, miracles and all the superlatives.

'He said he was for the people... I have met the people and you are not them.'

Describing the atmosphere at the march she said: 'This is the upside of the downside. This is an outpouring of energy and true democracy that I very never seen in my very long life. It is wide in age, it is deep in diversity and remember the constitution does not begin with "I the president" it begins with "we the people".'

'If you force Muslims to register, we will all register as Muslims.'

'This is a day that will change us forever because we are together,' she said.

White House press secretary Sean Spicer had no comment on the march except to note that there were no firm numbers for turnout because the National Park Service no longer provides crowd estimates.

Soul singer Maxwell was among the artists to perform onstage at the Women's March in Washington DC

Thousands wore pink hats as they showed their opposition to Donald Trump at the huge rally in Washington DC

Thousands took part in a protest against newly-inaugurated President Donald Trump in New York

Jodi Evans from Los Angeles, Calif., attends the Women's March on Washington on Independence Avenue

A demonstrator with a sign calling for more love and less hate takes part in the Women's March to the US Consulate in Amsterdam

Activists in the Netherlands mobilised to take part in the huge protest in Amsterdam on Saturday

Signs at the march in Bristol included the slogans 'We Reject The Comb-Over Con', 'Dump Trump' and 'Feminism is Pro-Human'.

The movement states on its website that the US election 'proved a catalyst for a grassroots movement of women to assert the positive values that the politics of fear denies'.

Marchers say they want to vent against an incoming administration they fear will roll back women's rights.

An estimated 100,000 protesters marched through central London - including Mayor Sadiq Khan - bringing the city to a standstill. Pictured is the crowds at Trafalgar Square

'Women's rights are humans rights,' one sign says, another reads 'woman's place is in the resistance'

The Women's March on London (pictured is Trafalgar Square) is being held in conjunction with others taking place in cities across the world to promote women's and human rights. Organisers announced on stage that 80,000 people had taken part in the event

Protesters make their way through the streets of London with a life size cut out of former President Barack Obama

Protesters carry placards in London in a march to promote women's rights in the wake of the US election result

Two young girls protest Donald Trump's presidency in Edinburgh, Scotland. A woman wears an apron with the slogan 'march for all woman kind'

Women sing at the 'March of Women against Trump' protest in Rome, Italy

In Rome women sang as they started to march again Trump on Saturday

A woman holds a banner stating 'I am a Nasty Woman' in Seattle (left), while thousands of demonstrators took to the streets of Atlanta (right)

Activist Sarah Annay Williamson holds a placard and shouts slogan during the Women's March rally in Kolkata, India

Demonstrators in Brussels lit candles in Brussels as they took part in a Women's March in the Belgian capital

The candlelit parade in Brussels was held in protest at Donald Trump's inauguration as US President

A Facebook event set up to advertise the event said: 'We will march, wherever we march, for the protection of our fundamental rights and for the safeguarding of freedoms threatened by recent political events.

'We unite and stand together for the dignity and equality of all peoples, for the safety and health of our planet and for the strength of our vibrant and diverse communities.'

Hours before the women's event in Washington began, people were streaming into the city, many wearing bright pink hats and wielding signs with messages such as 'The future is female' and 'Less fear more love.'

Rena Wilson, of Charlotte, North Carolina, said she hopes the women can send Trump a message that they're 'not going anywhere.'

Joy Rodriguez, of Miami, arrived with her husband, William, and their two daughters, ages 12 and 10.

'I want to make sure their rights are not infringed on in these years coming up,' Joy Rodriguez said.

March organizers said women are 'hurting and scared' as the new president takes office and want a greater voice for women in political life.

'In the spirit of democracy and honoring the champions of human rights, dignity and justice who have come before us, we join in diversity to show our presence in numbers too great to ignore,' their mission statement says.

Retired teacher Linda Lastella, 69, who came from Metuchen, New Jersey, said she had never marched before but felt the need to speak out when 'many nations are experiencing this same kind of pullback and hateful, hateful attitudes.'

'It just seemed like we needed to make a very firm stand of where we were,' she said.

Rose Wurm, 64, a retired medical secretary from Bedford, Pennsylvania, boarded a Washington-bound bus in Hagerstown, Maryland, at 7 a.m. carrying two signs: one asking Trump to stop tweeting, and one asking him to fix, not trash, the Obamacare health law.

'There are parts of it that do need change. It's something new, something unique that's not going to be perfect right out of the gate,' she said.

Protesters gather for the Women's March on Philadelphia a day after Republican Donald Trump's inauguration

Hundreds of people march in Leeds against US President Donald Trump on the first full day of his presidency

Hundreds of people march In Leeds with signs saying 'women's rights are human rights'

A woman holds a sign saying 'hands off my p***y' as she marches in central London

Mayor of London Sadiq Khan and his wife Saadiya were in Trafalgar Square, where protesters gathered ahead of a rally

Some women carried signs saying 'nasty woman' as they tried to reclaim the name that Trump gave Hillary Clinton during the final presidential debate in October.

The march attracted significant support from celebrities. America Ferrara led the artists' contingent, and those scheduled to speak in Washington included Scarlett Johansson, Ashley Judd, Melissa Harris-Perry and Michael Moore. The promised performance lineup included Janelle Monae, Maxwell, Samantha Ronson, the Indigo Girls and Mary Chapin Carpenter.

Women and other groups were demonstrating across the nation and as far abroad as Myanmar and Australia.

In Sydney, thousands of Australians marched in solidarity in Hyde Park. One organizer said hatred, bigotry and racism are not only America's problems.

Friday's unrest during the inauguration led police to use pepper spray and stun grenades to prevent the chaos from spilling into Trump's formal procession and the evening balls.

Protesters stream onto Independence Avenue at the Women's March on Washington

The protesters gathered in their thousands near Capitol Hill. Roughly 1,800 buses that have registered to park in Washington on Saturday. That translates into nearly 100,000 people coming for the march just by bus

Protestors hold a placard reading 'Respect for American women' during a 'Women's March' at the Old Port (Vieux Port) of Marseille, southern France

Demonstrators flooded a popular central Sydney park carrying placards with slogans including "Women of the world resist," `'Feminism is my trump card" and "Fight like a girl"

Protesters pose at the start of the Women's March on Main Street Park City on January 21, 2017 in Park City, Utah

Protesters burn an American flag in a rally against Donald Trump in Manila, in the Philippines

An estimated 7,000 people joined a rally in Oklahoma City to mark Donald Trump's first full day as US President

Thousands of protesters marched in Cleveland in one of dozens of rallies held in cities across the United States